Field of the Invention
This invention relates to a closure device.
Description of Related Art
A generic closure device includes a first closure part with at least one first connecting region and a second closure part with at least one second connecting region, which are to be connected with each other in the manner of a screw connection and can be transferred into a closed position in which the two closure parts are held at each other via their connecting regions. Correspondingly, for closing the closure device the first closure part is attachable to the second closure part along a connection axis and by rotation about the connection axis relative to the second closure part is movable into the closed position.
A closure device with two closure parts, which can be connected with each other in the manner of a screw connection, is known in principle in different forms. However, turning in of a closure part for closing the closure device in conventional screw connections regularly involves an increased expenditure of force, in order to securely arrest the two closure parts at each other. For release, a comparatively high force then must be applied as well. In addition, usual screw connections frequently are suitable for fast and uncomplicated opening only to a limited extent.
For this reason, closure devices with bayonet lock are used in the alternative, in which a closure part likewise is rotated about a connection axis relative to another closure part, in order to securely arrest the two closure parts at each other and close the closure device. In bayonet locks, however, it regularly is disadvantageous that the two closure parts must be aligned relative to each other very accurately, in order to put the parts of the bayonet lock into each other.
Furthermore, in closure devices in which for closing the closure device the two closure parts are connected with each other in the manner of a screw connection it regularly is disadvantageous that the connection cannot easily be secured against opening of the closure device. To prevent that one of the closure parts inadvertently is rotated relative to the other closure part in an opening direction and the connection herewith is released, additional components such as pins, cotter keys or latches regularly are used. However, especially in manually operable closure devices handling and comfort thereby are deteriorated.
From DE 10 2008 019 063 B4 there is furthermore known a closure device in which a first closure part latches with a second closure part and is held in a closed position via spring locking elements of the second closure part. The spring locking elements are movable radially with respect to the connection axis, along which the first closure part is guided to the second closure part.
In a closure device known from DE 10 2008 019 063 B4, the first closure part on attachment to the second closure part is automatically rotated relative to the second closure part by magnetic elements provided at the first and the second closure part into a position in which the magnets attract each other. Via the magnets, the first closure part then without rotation is pulled into the closed position along the connection axis, until the spring locking elements snap into place. Opening of the closure device then is possible, however, by rotating the first closure part. DE 10 2008 019 063 B4 describes that a closure device disclosed therein can have the tendency to unscrew under load. Inadvertent opening of the closure device can be counteracted, however, by suitable dimensions and strength of the magnets used.
Thus, DE 10 2008 019 063 B4 provides that opening of the closure device can be achieved by rotating the first closure part. In a closure device of DE 10 2008 019 063 B4, in contrast to a generic closure device, it is however not provided that the first closure part is movable relative to the second closure part into a closed position by rotation about the connection axis in the manner of a screw connection. Rather, the first closure part is pulled into the closed position along the connection axis and is latched at the second closure part by spring locking elements radially movable with respect to the connection axis. Moreover, DE 10 2008 019 063 B4 proposes to use larger or stronger magnets, in order to counteract an inadvertent opening of the closure device under load. In closures subjected to a higher load, however, such measure has its limits, as it is not possible to use magnets of any size, without this leading to a disproportionate increase of the dimensions of the closure device and its manufacturing costs.